Thank you very much for this. The function you provided works super fine, but only once!
If I call it in an onEnterFrame, here's what happens: http://pages.videotron.com/poubou/flash/cannes01.html Strange... or is it ? On 4/25/07 6:13 PM, "Joshua Sera" <[EMAIL PROTECTED]> wrote: > Actually, you're right. if your endpoints will never > move, you can still use a quadratic bezier. > > The percentage would be > > (mc._x - firstpoint.x)/(lastpoint.x - firstpoint.x) > > Since you're using curveTo, you already have all the > points you need for the formula Here's a function for > you: > > import flash.geom.Point; > > function getPoint(first:Point, last:Point, > control:Point, ratio:Number):Point { > var pReturn:Point = new Point(); > var b:Number = 1-ratio; > pReturn.x = (b*b*first.x) + (2*ratio*b*control.x) + > (ratio*ratio*last.x); > pReturn.y = (b*b*first.y) + (2*ratio*b*control.y) + > (ratio*ratio*last.y); > return pReturn; > } > > first if the first point in your curve, last is the > last, control is the point specified by the first two > arguments in the curveTo method. > > This will give you the closest point on the line to > your MC's position. If you only want to snap if the MC > is within a certain distance, just check the > difference of the ys of your mc's position, and the > returned point. > > > --- leolea <[EMAIL PROTECTED]> wrote: > >> On 4/25/07 5:31 PM, "Joshua Sera" >> <[EMAIL PROTECTED]> wrote: >> >>> If you know that the two endpoints of the curve >> are >>> always going to have an equal x or y value, the >> you >>> can just use the quadratic formula, and get the >> right >>> Y value. >> >> The two endpoints will never move. The middlepoint >> will be the only one >> moving. >> >> So now I just need the quadratic formula ... I >> googled "quadratic formula" >> and I couldn't figure it out nor translate it to my >> Flash needs. >> >> Like I said, I'm (almost) totally math impaired ! >> >>> If the endpoints are arbitrary, it's a bit more >>> complicated. Bezier curves take a number from 0 to >> 1 >>> and give you a point along the curve. Plugging 0 >> into >>> the formula gives you the first endpoint, 1 gets >> you >>> the last, and anything else gives you something in >>> between. >>> >>> This means you're going to have to figure out >> where >>> along the curve your MC is closest to, which >> involves >>> some vector math. >>> >> >> Since I know the _x position of MC, in order to >> figure out where the MC is >> along the curve... Can't I use its _x "percentage": >> >> MC._x / (lastpoint.x - firstpoint.x) >> >> Just curious, but I don't think I need this since my >> two endpoints will not >> move. >> >>> If you want, I can draw out the way I'd approach >> it. >> >> Of course I'd be more than happy to see that. >> >> >> >> >> _______________________________________________ >> Flashcoders@chattyfig.figleaf.com >> To change your subscription options or search the >> archive: >> > http://chattyfig.figleaf.com/mailman/listinfo/flashcoders >> >> Brought to you by Fig Leaf Software >> Premier Authorized Adobe Consulting and Training >> http://www.figleaf.com >> http://training.figleaf.com >> > > > __________________________________________________ > Do You Yahoo!? > Tired of spam? Yahoo! Mail has the best spam protection around > http://mail.yahoo.com > _______________________________________________ > Flashcoders@chattyfig.figleaf.com > To change your subscription options or search the archive: > http://chattyfig.figleaf.com/mailman/listinfo/flashcoders > > Brought to you by Fig Leaf Software > Premier Authorized Adobe Consulting and Training > http://www.figleaf.com > http://training.figleaf.com _______________________________________________ Flashcoders@chattyfig.figleaf.com To change your subscription options or search the archive: http://chattyfig.figleaf.com/mailman/listinfo/flashcoders Brought to you by Fig Leaf Software Premier Authorized Adobe Consulting and Training http://www.figleaf.com http://training.figleaf.com
